OPINION: There is a sanctimonious tone to the criticism of Sonny Bill Williams.

The public reaction to his decision to play in Japan then return to the NRL has highlighted how blinkered many people are when it comes to the All Blacks.

Yes, it's important, but it is not exclusive.

Becoming an All Black is not a life sentence. It is not a cult.

Williams, like every professional, has his reasons and should not have to justify them to all and sundry.

Jerome Kaino headed to Japan in his prime to secure his young family's future and prolong his body's ability to cope with the rigours of professional rugby.

Williams says the money was simply too big to ignore in Japan, and that he'd given someone his word he would play rugby league next year.

Why the bitterness to one, but not the other?

It seems the stigma of walking out on the Bulldogs mid-season 2008 has stuck and that's fair enough to a degree, but Williams has never come across as the dishonest or deceptive type.

He has expressed a desire to return to the All Blacks if good enough and there's no reason to think he could not.

But with Williams it seems a different set of judgments are applied. He is painted in some quarters as a money-hungry mercenary.

Has anybody considered he might just miss playing rugby league? It's a popular sport. Brad Thorn missed it enough to go back for a stint with the Brisbane Broncos.

And will there be such an uproar if, and when, Richie McCaw or Dan Carter take sabbaticals to play overseas before the next World Cup?

It seems being different equates to dividing opinion in New Zealand. Williams' manager Khoder Nasser's job is to maximise his clients' market value and in that he is doing a sterling job.

SBW is a brand like few others.

Unlike most of us he has a myriad of exciting doors to choose from and the speculation that surrounds his career ensures they are rarely locked.

The job description reads: lucrative overseas job in exciting and challenging new field of work. One year, no strings, and you go with your former employer's blessing.

How many in their mid-20s would turn such opportunities down?

Professional sports is a week-by-week profession. Just ask Williams' Chiefs midfield partner Richard Kahui how certain he feels about his future in the game.

For those who say Williams' won't have a legacy, nonsense.

A sportsman's legacy comes down to the sum of their achievements.

What if Williams wins the Super Rugby title in a few weeks time, a second NRL title, a few tests for the Kiwis, returns to bag a second Rugby World Cup as a senior All Black and knocks out a few boxers along the way?

Only time will tell, but it would be a near-unrivalled legacy.

And for those wondering why the NZRU has sent him off with a friendly hug, isn't it obvious?

He's been a walking publicity machine for rugby union since he arrived in Christchurch.

And as a bonus he's played the house down.

If he comes back, the NZRU is in a position to simply turn the tap back on. Why would it jeopardise that now?

Their only real concern is that many of us, probably plenty of the knockers included, will be tuning in to a few Roosters matches next season.

- © Fairfax NZ News